Help with MA research.

I am studying an education module on wellbeing and aspiration. I want to look at what schools can do to motivate greater cognitive development in middle to higher ability children (not g and t). Can anybody suggest any articles/books/authors who address this issue in their work please. Despite spending hours searching online I have found nothing that really addresses this issue. I would be eternally grateful if someone could point me in the right direction.

Sorry if this is off-beam, but concentrating on your phrase "wellbeing and aspiration", Wellington College introduced a course several years ago on Wellbeing. They have been running it for seven years now so they might have some information on how the school differentiates the lessons for different ability groups.